http://www.dropwizard.io/2.0.18/dropwizard-bom/dropwizard-dependencies/dropwizard-parent/dropwizard-validation: Dropwizard is a Java framework for developing ops-friendly, high-performance, RESTful web applications.
  • Coda Hale
  • Nick Telford
  • Graham O'Regan
  • Ryan Kennedy
  • Camille Fournier
  • Carlo Barbara
  • Matt Veitas
  • Ryan Tenney
  • Jochen Schalanda
  • Glenn McAllister
  • Nick Babcock
  • Justin Plock
  • Artem Prigoda 
package io.dropwizard.validation;

import javax.validation.Constraint;
import javax.validation.Payload;
import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;


Validates a bean predicate method as returning true. Bean predicates must be of the form isSomething or they'll be silently ignored. 
/**
 * Validates a bean predicate method as returning true. Bean predicates must be of the form
 * {@code isSomething} or they'll be silently ignored.
 */
@Target({TYPE, ANNOTATION_TYPE, METHOD})
@Retention(RUNTIME)
@Constraint(validatedBy = MethodValidator.class)
@Documented
public @interface ValidationMethod {
    String message() default "is not valid";

    Class<?>[] groups() default {};

    @SuppressWarnings("UnusedDeclaration") Class<? extends Payload>[] payload() default { };
}